Berkley is an American medical doctor and epidemiologist. He joined GAVI - the Vaccine Alliance, as its CEO in August 2011. Founder and former President and CEO of the International AIDS Vaccine Initiative (IAVI), Dr Berkley is a Harvard-trained physician, CDC-trained epidemiologist and a leading global vaccines advocate. Created in 2000, GAVI is an international organisation that focuses on protecting the world’s poorest children by improving access to new and underused vaccines. It brings together developing country and donor governments, the World Health Organisation, UNICEF, the World Bank, the vaccine industry in both industrialised and developing countries, research and technical agencies, civil society, the Bill & Melinda Gates Foundation, and other private philanthropists, and has observer status at the World Health Assembly.